My wife is not affectionate

I figured I'd see what the great people of reddit have to say. We've been married for 18 years, no kids, I'm 40 and she is 42. We do well financially together, have a nice home and drive nice cars. She has never been that affectionate but maybe I'm just noticing it more and I'm feeling a void in our relationship. For example, I just returned home from a 3 day work trip (I don't travel much for work) I come in the house and she is in the living room. I guess I just imagine her getting up to great me, give me a hug, maybe a kiss and she just stays there, sitting on the couch and says "you made it" Ugh.. We can probably go a month or more without a kiss and if there is one, I 100% initiated it. Last week we were sitting on the couch, her on one side, me on the other with a cushion between us. I laid down putting my head on her lap to snuggle and she just says "don't lay on me, you're heavy"

Frequency of sex is not the issue here, we have sex 2-4 times a week but it's pretty vanilla and always has been. All of it is 100% initiated by me. I can count on one hand how many times during our 21 years together that she initiated. There is no foreplay, she doesn't care for it, she thinks giving or receiving oral is gross. I'm thankful for the frequency as I've heard from friends how little them and their spouses have sex.

I guess I just want more from our relationship. I've brought it up numerous times over the years but she avoids any sort of conflict at all cost. She just shuts down if you bring up anything. I've told her before that I question if she even loves me and of course she reassures me that she does. I realize that the grass is always greener on the other side of the fence and I have a ton to be grateful for. Any advice or things I should be asking or doing?